1. Field of the Invention
The present invention relates to construction materials and methods and more particularly to a method for building using glass blocks and to a device for use with the method.
2. Description of the Related Art
Glass blocks have become increasingly popular in construction work and also in connection with the architectural decoration of both private dwellings and office or industrial buildings. In this context “glass block” is a generic term for generally right-angled, square or rectangular building blocks consisting basically of two sheets of glass that have been fused together. The sheets of glass may be patterned, rough, smooth and more or less transparent or translucent.
There is an air-filled cavity between the sheets of glass, which provides the glass block with good insulating properties both for sound and heat insulation. For this reason, such blocks are increasingly used for exterior walls or “windows” as well as for internal walls and partitions.
Because of the way they are made, even though they have high levels of rigidity and strength, glass building blocks of this kind are exposed to certain limitations as regards load. These limitations are largely determined by the skill and care with which the wall is assembled.
The classical building method when building with such glass blocks has been to lay a first course or layer of blocks with mortar between adjacent blocks. A layer of mortar is then laid along the top surface, followed by a second course of blocks. It has then been necessary to wait until an extensive degree of setting or hardening has taken place before further courses can be laid. Such methods of building are time-consuming and protracted.
More recently, alternative methods of building have been developed in which spacer members are placed between adjacent glass blocks. These spacer members may be formed of metal or plastics and are adapted to the edge profiles of the blocks. They are also carefully dimensioned to ensure the desired spacing between courses and also between adjacent blocks on the same course. Various different methods have been used to maintain the blocks together. According to the disclosure of U.S. Pat. No. 5,484,702, an assembly of glass blocks provided with spacers may be completely surrounded by a metal or polyester strip, which serves to bind them together. Such a construction is inherently impractical and relies on the successful tensioning of the strip. The possibility of building curved walls incorporating such a strip is not foreseen.
It has also been proposed to use spacing strips provided with recesses or channels for receiving a sealant or silicone caulking agent. Such arrangements allow the glass blocks to be effectively glued together using the sealant. Because the spacing between the blocks is determined by the spacing strip, it is possible to build a complete wall in one procedure without the inconvenience of waiting for mortar to harden. The sealant provides the required strength after drying and further rigidity is provided by grout applied to the joints between the glass blocks thereby covering the edges of the spacing strips. A method of building using such spacing strips and sealant has been previously disclosed in WO02/12651.
Prior art spacing strips are of a generally solid construction. A commonly used material in the past has been wood or wood composite. While such constructions have been found to provide the necessary strength for support of glass block walls, they have been found to be adversely affected by moisture. Alternative spacing strips have been considered using plastics materials but these have been found relatively heavy and expensive to produce due to the amount of material required. Additionally, problems have been encountered in achieving the necessary strength required to meet various building standards. In this respect, the strength of the spacing strip in compression and shear and the strength of the bond between the spacing strip and the adhesive medium and between the adhesive medium and the glass block must all meet the required standards.